Uneven hips, also known as pelvic asymmetry or lateral pelvic tilt, occur when the pelvis is not level, causing one hip bone to sit higher than the other. This common condition can range in severity; it may be asymptomatic or lead to chronic musculoskeletal issues. Since the pelvis is the foundation for the spine and the attachment point for the legs, any misalignment can disrupt the body’s entire kinetic chain. Understanding the underlying cause of this imbalance is the first step toward appropriate management and relief.
Why Hips Become Uneven
The causes of uneven hips are classified into two categories: structural and functional. A structural cause is rooted in a true anatomical difference in bone length, known as Leg Length Discrepancy (LLD). This means the bones of the femur or tibia are measurably shorter on one side, which is confirmed through imaging.
Structural LLD can be congenital or acquired later in life. Acquired causes often include trauma, such as a poorly healed fracture, or damage to growth plates during childhood. While structural differences of less than 10 millimeters are common and often asymptomatic, greater discrepancies typically result in noticeable pelvic tilting.
Functional causes create an illusion of uneven hips where the underlying bone lengths are equal. This apparent discrepancy arises from muscular imbalances, joint restrictions, or poor postural habits. For example, habitually shifting weight onto one leg or prolonged asymmetric sitting can lead to certain muscles becoming tight and others becoming weak.
Tight muscles, particularly the hip flexors, piriformis, or the quadratus lumborum, can pull the pelvis into a rotated or elevated position. Additionally, conditions like scoliosis—a sideways curvature of the spine—can exert uneven forces on the pelvis, causing it to tilt. Functional issues are generally responsive to corrective exercise and manual therapies.
Common Symptoms Associated with Uneven Hips
The body compensates for pelvic asymmetry, which often leads to discomfort and pain in areas far from the hip. A frequently reported issue is chronic lower back pain, which can be localized or radiate toward the hips and buttocks. This pain often increases after long periods of standing or walking as the body struggles to maintain balance.
Changes in gait, or walking pattern, are common as the body tries to minimize the functional difference in leg length. This compensatory movement can strain joints below the pelvis, resulting in knee, ankle, or foot pain. The uneven loading can also accelerate wear and tear, potentially contributing to joint degeneration.
Visible postural deviations affect the upper body as well. A person may notice that one shoulder appears lower than the other, or that their head seems slightly tilted to one side. Clothing may also hang unevenly, with pant legs or sleeves appearing longer on one side.
How Healthcare Professionals Diagnose Pelvic Asymmetry
Diagnosing pelvic asymmetry requires a systematic approach to determine if the cause is structural or functional. The initial step involves a physical examination, where a professional visually assesses posture and gait. The clinician will palpate bony landmarks, such as the iliac crests, to check for height differences while the patient is standing.
This assessment is followed by a functional assessment, which involves analyzing movement patterns. Tests like the supine-to-sit test or analyzing a patient’s squat help identify muscle imbalances and joint restrictions contributing to functional asymmetry. Movement analysis helps pinpoint specific muscles that are tight or weak.
To confirm a true structural LLD, imaging techniques are employed for definitive measurement. A specialized X-ray, known as a scanogram or standing full-length X-ray, is taken to accurately measure the length of the femur and tibia bones. This imaging is crucial for distinguishing between an anatomical and a functional difference, which guides the treatment plan.
Correcting and Managing Uneven Hips
The management strategy for uneven hips depends entirely on whether the cause is functional or structural. For functional asymmetry, the primary intervention is physical therapy aimed at correcting muscular imbalances and improving posture. This approach focuses on releasing overactive muscles that are pulling the pelvis out of alignment.
Targeted stretching exercises lengthen tight muscles, such as the hip flexors, piriformis, and quadratus lumborum. Simultaneously, strengthening exercises stabilize the pelvis by building strength in the core, gluteal muscles, and hamstrings. Consistency with these corrective exercises can reduce the apparent length difference and related symptoms.
For structural LLD, especially differences exceeding 10 millimeters, non-surgical interventions equalize the leg length. This typically involves using a heel lift or a custom orthotic placed inside the shoe of the shorter leg. These external devices compensate for the anatomical difference, leveling the pelvis and reducing strain on the spine and lower extremity joints.
Surgical intervention, such as limb lengthening or growth plate modification, is generally reserved for severe structural discrepancies, usually those greater than 5 centimeters. The decision to treat depends on the extent of the discrepancy, the patient’s age, and the severity of the associated symptoms. Addressing the functional components remains a valuable part of treatment, even when a structural difference exists.